Hey Bob,
Don't believe everything you read.
In the Spanish Civil War, the I-16's didn't meet any Bf 109F's. They fought Bf 109B and C models, and weren't overwhelmed by the Bf 109, but by the numbers of them. Individually, the I-16 was a match for the Bf 109 B / C as an aircraft. Whether or not it was during the fight was determined by the pilots. The I-16 was quite good, but had reached its development potential while the Bf 109 was just getting developed into a combat-ready fighter. With the arrival of the Emil model, the I-16 was outclassed.
The Soviet Union stayed with the I-16 longer than was advisable and, by the time it DID meet with the Bf 109F on the Russian Front, it WAS oboslescent. They continued with it while they developed the Yaks, Lavochkins, and MiGs. And the Soviet Union didn't get shot down in droves in the 1943 - 1945 timeframe ... that's when THEY shot down a LOT of Germans.
That's what my readings have indicated and that's what was said to be by several former WWII Russian pilots as well as at least 3 more modern former Soviet pilots who were out of the cockpit and visiting the USA to purchase modems for their communication network said. One in particular said his instructors, who were former WWII fighter pilots, said that while the Germans frollicked early in the war, the Soviet pilots would hunt them down in packs after mid-1943. The Soviets particularly enjoyed attacking German airfields in bad weather when the Germans were grounded but the Soviets were operating. By summer of 1944, the Germans were still there, but were basically being systematically eliminated as they were found. By early 1945, they were almost gone on the Russian Front and only a small handful were still operational. Near the end, the resistance that existed was almost all ground forces with only the occasional odd German fighter to deal with.
Numbers aside (accurate records for them don't exist in Russia), the Soviet Air Force after mid-1943 was a better force than the Luftwaffe, especially at lower altituides where they mostly operated. The MiG-3 was one of the few higher-altitude fighters in Soviet service. Most of the rest had single-stage superchargers and were good up to about 16,000 - 18,000 feet, after which the Bf 109 and Fw 190 had the edge. So the Soviets declined to go up and fight, instead prefgerring to attack German troops and force the Luftwafee down to fight. It worked and the Luftwaffe was slowly worn down in the last year and a half of the war.
Coincidentally, during this same period, the germans pilots in the west were also becomming less capable and less trained. We know their pilot quality declined in the West ... does anyone really think they sent the better pilots to the Russian Front an saved the new, green guys to defend the Reich? It also declined in the East as the Soviets got better planes and better tactics. Sorry, the Luftwaffe wasn't the best in the world in mid-1944 and was in decline everywhere while still being able to field the occasional good day filled with exploits of the "experts." Years of war will do that to you when the supply of pilots isn't keeping up with attrition.